Ketamine is FDA Approved for use as an anesthetic in surgical settings.

Ketamine is not (yet) FDA Approved for the following conditions, however increasing scientific evidence is accumulating that it may be safe and effective. At this time, the use of ketamine for these disorders is 'off label' 

Off label drug use (OLDU) is both legal and common. In fact some medications, are used more for off label than approved conditions (eg gabapentin & amitriptyline both >80%)

On the one hand, in the ideal world, every use of medication would be supported by high quality scientific evidence. On the other hand, in the real world, each patient is unique and waiting for adequate scientific evidence or FDA approval would deprive physicians and patients the use of helpful treatments.

We believe that use of ketamine for psychiatric conditions is reasonable under some circumstances because 1) the safety is excellent 2) the effectiveness, although not durable or dependable, can help some people.